WASHINGTON - Western powers today prepared a tough response to Russia's military advance into Ukraine and warned that Moscow could face economic penalties, diplomatic isolation and bolstered allied defenses in Europe unless it retreats.
The crisis may prove to be a game-changer for President Barack Obama's national security policy, forcing him to give up his foreign policy shift to Asia and to maintain U.S. troop levels in Europe to limit Russia's reach.
The ill will and mistrust also could spill over on two other global security fronts - Syria and Iran - where Russia has been a necessary partner with the West.
Russian President Vladimir Putin gave no indication that he would heed the West's warnings. Hundreds of armed men surrounded a Ukrainian military base in Crimea. In Kiev, Ukraine's capital, Prime Minister Arseniy Yatsenyuk alerted allies that "we are on the brink of disaster."
Secretary of State John Kerry said he has consulted with other world leaders, and "every single one of them are prepared to go to the hilt in order to isolate Russia with respect to this invasion."
He was considering a stop in Kiev during his trip this week to Paris and Rome for discussions on Lebanon and Syria.
In Brussels, NATO's secretary-general, Anders Fogh Rasmussen, said Russia's actions have violated a U.N. charter. He said the alliance was re-evaluating its relationship with Russia.
"There are very serious repercussions that can flow out of this," Kerry said.
Beyond economic sanctions and visa bans, freezing Russian assets, and trade and investment penalties, Kerry said Moscow risks being booted out of the powerful Group of Eight group of world powers as payback for the military incursion.
Several senators also called for bolstered missile defense systems based in Poland and the Czech Republic.